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PMI Foam Core (Rohacell) A (Solution annealed)

Temper

also ROHACELL

Use where FAR 25.853 heat-release, smoke and toxicity requirements apply (cabin interiors, ducts).

High cost $$$$

Values for the A condition

Other PMI Foam Core (Rohacell) grades and fills

PMI Foam Core (Rohacell) is listed in 14 conditions; see the grade overview at PMI Foam Core (Rohacell).

Compare all 14 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
32 kg/m³ fine-cell industrial grade
Lowest density; radome and lightweight non-structural cores where stiffness demand is low.—13.5—
52 kg/m³ fine-cell industrial grade
Most common general-purpose density for prepreg sandwich panels and antenna structures.—23—
52 kg/m³ high-temperature aerospace grade
Pick WF over IG when the part is autoclave co-cured at 180 °C / high pressure and qualified aerospace data are needed.—24.5—
High energy absorption / damage tolerant grade
Choose when impact damage tolerance and crush energy absorption matter more than peak stiffness (leading edges, crash structures).—28—
High-frequency / radome dielectric grade
Tightly controlled low dielectric constant and loss tangent for radomes and antenna sandwich panels.—23.5—
in-mould foamable (particle) grade
Foamed directly into complex 3D cavities for high-volume parts, avoiding block machining and scrap.—23—
AThis page
Solution annealed
Use where FAR 25.853 heat-release, smoke and toxicity requirements apply (cabin interiors, ducts).—23—
71IG-FDefault
75 kg/m³ fine-cell industrial grade
Default workhorse density: good shear strength/weight balance for structural sandwich skins and sporting goods.—23—
75 kg/m³ high-temperature aerospace grade
Standard aerospace core density for 180 °C epoxy prepreg co-cure at up to 0.7 MPa.—24.5—
110 kg/m³ fine-cell industrial grade
Higher density for locally loaded areas, inserts, hardpoints and thin skins with high pressure cure.—43—
110 kg/m³ high-temperature aerospace grade
For high-pressure autoclave cure and heavily loaded sandwich zones (helicopter blades, control surfaces).—44.5—
S / HT
For BMI/high-Tg epoxy cures and service above 180 °C where standard WF would creep or collapse.—44.5—
205 kg/m³ high-density aerospace grade
High-density core for local load introduction, bearing pads and high-pressure cure cycles.—74.5—
300 kg/m³ maximum-density grade
Densest PMI block; used as machinable structural filler/insert material replacing hardwood or syntactic.—113.5—

What is PMI Foam Core (Rohacell) A?

PMI Foam Core (Rohacell) A is PMI Foam Core (Rohacell) in the A temper — use where FAR 25.853 heat-release, smoke and toxicity requirements apply (cabin interiors, ducts). PMI Foam Core (Rohacell) A has a tensile strength of 2 MPa (0.29 ksi), weaker than 92% of composite grades. Elongation at break is 3% and the elastic modulus is 0.09 GPa (0.0123 Msi). PMI Foam Core (Rohacell) A has a density of 0.08 g/cm³ (0.0027 lb/in³), lighter than 91% of composite grades. Its glass-transition temperature is 210°C (410 °F). 71IG-F is the default condition FabDigit quotes; A is available on request or by drawing note.

Advantages

  • Lightweight — 0.08 g/cm³ (0.0027 lb/in³), better than 91% of composite grades
  • Easy to machine — 85/100, better than 90% of composite grades
  • Ductile — tolerates forming and impact — 3%, better than 75% of composite grades

Limitations

  • Poor heat conductor — 0.03 W/m·K (0.0191 BTU/hr·ft·°F), worse than 96% of composite grades
  • Low stiffness — 0.09 GPa (0.0123 Msi), worse than 93% of composite grades
  • Degrades in UV without stabilisers — 25/100, worse than 86% of composite grades

PMI Foam Core (Rohacell) A properties

Typical room-temperature values for PMI Foam Core (Rohacell) A; 14 are specific to this condition. Other listed values are PMI Foam Core (Rohacell) reference data and may not represent this condition. Bars are the position among composite grades.

Physical2

PMI Foam Core (Rohacell) A has a density of 0.08 g/cm³ (0.0027 lb/in³), lighter than 91% of composite grades. Its glass-transition temperature is 210°C (410 °F).

Density0.08 g/cm³0 lb/in³
Glass Transition (Tg)210°C410 °F

Mechanical8

PMI Foam Core (Rohacell) A has a tensile strength of 2 MPa (0.29 ksi), weaker than 92% of composite grades. Elongation at break is 3% and the elastic modulus is 0.09 GPa (0.0123 Msi).

Elastic (Young's) Modulus0.09 GPa0.01 Msi
Shear Modulus0.03 GPa0 Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)2 MPa0.29 ksi
Elongation at Break3%
Compressive Strength2 MPa0.22 ksi
Compressive Modulus0.09 GPa0.01 Msi
Shear Strength1 MPa0.17 ksi

Thermal7

PMI Foam Core (Rohacell) A is rated for continuous service to 180°C (356 °F). It conducts heat at 0.03 W/m·K (0.0191 BTU/hr·ft·°F), worse than 96% of composite grades. Thermal expansion is 35 µm/m·K (19.4 µin/in·°F).

Thermal Conductivity0.03 W/m·K0.02 BTU/hr·ft·°F
Specific Heat Capacity1,500 J/kg·K0.36 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)35 µm/m·K19.4 µin/in·°F
Max Service Temperature (continuous)180°C356 °F
Min Service Temperature-196°C-321 °F
Flammability (UL 94)Qualified to FAR/JAR 25.853 (OSU 65/65, smoke density) for cabin applications; not a UL 94 V-rated compound.
Max Service Temperature (short-term)200°C392 °F

Electrical2

Dielectric Constant (1 MHz)1.1
Dissipation Factor (1 MHz)5×10⁻⁴

Chemical & Environmental2

UV resistance is poor.

UV / Weathering ResistancePoor25/100
Chemical Resistance SummaryStable to styrene, epoxy and most prepreg resins, water, dilute acids/alkalis and aliphatic solvents; attacked by strong polar solvents (ketones, esters, chlorinated solvents) and concentrated acids. Hygroscopic — must be dried before autoclave co-cure.

Sustainability3

Producing a kilogram of PMI Foam Core (Rohacell) A takes about 130 MJ of energy and emits 6.5 kg of CO₂ — less than 56% of composite grades. Typical recycled content is 0%.

Embodied Energy (primary production)130 MJ/kg55,890 BTU/lb
Embodied Carbon (primary production)6.5 kg CO₂/kg
Typical Recycled Content0%

Manufacturability1

PMI Foam Core (Rohacell) A's machinability is excellent (85/100, better than 90% of composite grades).

MachinabilityExcellent85/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with PMI Foam Core (Rohacell) A

Is PMI Foam Core (Rohacell) easy to machine?

CNC mills, saws, hot-wire and abrasive-waterjet cut easily with sharp uncoated tools and vacuum hold-down; use dust extraction and avoid melting from tool rubbing.

Can PMI Foam Core (Rohacell) be welded?

Not weldable; blocks are joined by epoxy/film-adhesive bonding or thermal splicing of billets before machining.

Can PMI Foam Core (Rohacell) be formed, bent or molded?

Thermoformable above ~180 °C over a tool for curved skins; must be oven-dried (e.g. 100–130 °C) before autoclave co-cure to prevent blistering and skin disbonds.

What surface finishes work on PMI Foam Core (Rohacell)?

Cell faces are open after machining — seal with film adhesive, surfacing film or low-density filler paste before painting or resin infusion.

PMI Foam Core (Rohacell) chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
methacrylic acid (units)co-monomer, imidized during foaming45 – 5550
methacrylonitrile (units)co-monomer; ring-closes to methacrylimide45 – 5550
blowing agent / additivesalcohol/formamide type blowing agent, FR additives in A grades0 – 52

PMI Foam Core (Rohacell) A — frequently asked

What is PMI Foam Core (Rohacell) A used for?

PMI Foam Core (Rohacell) A is typically used for aircraft radomes and control surfaces, formula 1 composite panels, satellite structures and medical imaging tables. In short: highest-temperature structural foam; autoclave co-curable core; best specific strength foam.

What is the tensile strength of PMI Foam Core (Rohacell) A?

PMI Foam Core (Rohacell) A has a typical tensile strength of 2 MPa (0.29 ksi) — weaker than 92% of composite grades. Strength varies by condition: see the 14 listed tempers.

Is PMI Foam Core (Rohacell) A easy to machine?

Yes — machinability is rated excellent (85/100, better than 90% of composite grades). CNC mills, saws, hot-wire and abrasive-waterjet cut easily with sharp uncoated tools and vacuum hold-down; use dust extraction and avoid melting from tool rubbing.

Can PMI Foam Core (Rohacell) A be welded?

Not weldable; blocks are joined by epoxy/film-adhesive bonding or thermal splicing of billets before machining.

What surface finishes work on PMI Foam Core (Rohacell) A?

Cell faces are open after machining — seal with film adhesive, surfacing film or low-density filler paste before painting or resin infusion.

Can PMI Foam Core (Rohacell) A be formed, bent or molded?

Thermoformable above ~180 °C over a tool for curved skins; must be oven-dried (e.g. 100–130 °C) before autoclave co-cure to prevent blistering and skin disbonds.

What is the maximum service temperature of PMI Foam Core (Rohacell) A?

PMI Foam Core (Rohacell) A is rated for continuous use to about 180°C (356 °F), and briefly to 200°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ROHACELL IG / IG-F product information — Evonik Industries (2023)
  2. ROHACELL WF product information — Evonik Industries (2023)
  3. ROHACELL HERO / RIST / Triple F technical brochures — Evonik Industries (2022)
  4. ASTM C365 / C273 / D1621 — sandwich core compressive and shear test methods — ASTM (2022)
  5. ASM Handbook Vol. 21: Composites — sandwich core materials — ASM International (2001)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.